U.S. Pat. No. 8,090,194 entitled “3D geometric modeling and motion capture using both single and dual imaging” discloses a method and apparatus for obtaining an image to determine a three dimensional shape of a stationary or moving object using a bi dimensional coded light pattern having a plurality of distinct identifiable feature types. The coded light pattern is projected on the object such that each of the identifiable feature types appears at most once on predefined sections of distinguishable epipolar lines. An image of the object is captured and the reflected feature types are extracted along with their location on known epipolar lines in the captured image. Displacements of the reflected feature types along their epipolar lines from reference coordinates thereupon determine corresponding three dimensional coordinates in space and thus a 3D mapping or model of the shape of the object can be obtained.
U.S. Pat. No. 8,208,719 entitled “3D geometric modeling and motion capture using both single and dual imaging” discloses a method and apparatus for obtaining an image to determine a three dimensional shape of a stationary or moving object using a bi dimensional coded light pattern having a plurality of distinct identifiable feature types. The coded light pattern is projected on the object such that each of the identifiable feature types appears at most once on predefined sections of distinguishable epipolar lines. An image of the object is captured and the reflected feature types are extracted along with their location on known epipolar lines in the captured image. Displacements of the reflected feature types along their epipolar lines from reference coordinates thereupon determine corresponding three dimensional coordinates in space and thus a 3D mapping or model of the shape of the object can be obtained.
U.S. Pat. No. 8,538,166 entitled “3D geometric modeling and 3D video content creation” discloses a system, apparatus and method of obtaining data from a 2D image in order to determine the 3D shape of objects appearing in the 2D image, the 2D image having distinguishable epipolar lines, the method comprising: (a) providing a predefined set of types of features, giving rise to feature types, each feature type being distinguishable according to a unique bi-dimensionally formation; (b) providing a coded light pattern comprising multiple appearances of the feature types; (c) projecting the coded light pattern on the objects such that the distance between epipolar lines associated with substantially identical features is less than the distance between corresponding locations of two neighboring features; (d) capturing a 2D image of the objects having the projected coded light pattern projected thereupon, the 2D image comprising reflected the feature types; and (e) extracting: (i) the reflected feature types according to the unique bi-dimensionally formations; and (ii) locations of the reflected feature types on respective the epipolar lines in the 2D image.
In the article “Range image acquisition with a single binary-encoded light pattern” by P. Vuylsteke and A. Oosterlinck (IEEE Transactions on Pattern Analysis and Machine Intelligence (PAMI), Volume 12, Issue 2, Pages 148-164, February 1990), the problem of strike identification in range image acquisition systems based on triangulation with periodically structured illumination is discussed. A coding scheme is presented based on a single fixed binary encoded illumination pattern, which contains all the information required to identify the individual strikes visible in the camera image. Every sample point indicated by the light pattern is made identifiable by means of a binary signature, which is locally shared among its closest neighbors. The applied code is derived from pseudonoise sequences, and it is optimized so that it can make the identification fault-tolerant to the largest extent. A prototype measurement system based on this coding principle is presented. Experimental results obtained with the measurement system are also presented.
In the article “Recent progress in coded structured light as a technique to solve the correspondence problem: a survey” by J. Batlle, E. Mouaddib and J. Salvi (Pattern Recognition, Volume 31, Issue 7, Pages 963-982, 31 Jul. 1998), the authors present a survey of significant techniques, used in the few years prior to the publication of the article, concerning the coded structured light methods employed to get 3D information.
In the article “Pattern codification strategies in structured light systems” by J. Salvi, J. Pages and J. Batlle (Pattern Recognition, Volume 37, Issue 4, Pages 827-849, April 2004) there is a discussion of the use of coded structured light for recovering the surface of objects. This technique is based on projecting a light pattern and viewing the illuminated scene from one or more points of view. Since the pattern is coded, correspondences between image points and points of the projected pattern can be easily found. The decoded points can be triangulated and 3D information is obtained. The authors present an overview of the existing techniques, as well as a new and definitive classification of patterns for structured light sensors. The authors have implemented a set of representative techniques in this field and present some comparative results. The advantages and constraints of the different patterns are also discussed.
In the article “A state of the art in structured light patterns for surface profilometry” by J. Salvi, S. Fernandez, T. Pribanic and X. Llado (Pattern Recognition, Volume 43, Issue 8, Pages 2666-2680, August 2010), shape reconstruction using coded structured light is discussed. Having a calibrated projector-camera pair, a light pattern is projected onto the scene and imaged by the camera. Correspondences between projected and recovered patterns are found and used to extract 3D surface information. This paper presents a review and a classification of the existing techniques. Some of these techniques have been implemented and compared, obtaining both qualitative and quantitative results. The advantages and drawbacks of the different patterns and their potentials are discussed.
International patent application serial number WO2008/062407 entitled “3d geometric modeling and 3d video content creation” discloses a method and apparatus for obtaining an image to determine a three dimensional shape of a stationary or moving object using a bi dimensional coded light pattern having a plurality of distinct identifiable feature types. The coded light pattern is projected on the object such that each of the identifiable feature types appears at most once on predefined sections of distinguishable epipolar lines. An image of the object is captured and the reflected feature types are extracted along with their location on known epipolar lines in the captured image. The locations of identified feature types in the 2D image are corresponded to 3D coordinates in space in accordance to triangulation mappings. Thus a 3D mapping or model of imaged objects is obtained.